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281.
Xiangming Li Yujian Zhang Li Jing Zongming Fu Ou Ma Jishna Ganguly Nilesh Vaidya Richard Sisson Jennifer Naginskaya Avinash Chinthala Minggang Cui Ryan Yamagata Mark Wilson Matthew Sanders Zihao Wang Paola Lo Surdo Marcin Bugno 《Biotechnology progress》2020,36(2):e2914
Mammalian cell line generation typically includes stable pool generation, single cell cloning and several rounds of clone selection based on cell growth, productivity and product quality criteria. Individual clone expansion and phenotype-based ranking is performed initially for hundreds or thousands of mini-scale cultures, representing the major operational challenge during cell line development. Automated cell culture and analytics systems have been developed to enable high complexity clone selection workflows; while ensuring traceability, safety, and quality of cell lines intended for biopharmaceutical applications. Here we show that comprehensive and quantitative assessment of cell growth, productivity, and product quality attributes are feasible at the 200–1,200 cell colony stage, within 14 days of the single cell cloning in static 96-well plate culture. The early cell line characterization performed prior to the clone expansion in suspension culture can be used for a single-step, direct selection of high quality clones. Such clones were comparable, both in terms of productivity and critical quality attributes (CQAs), to the top-ranked clones identified using an established iterative clone screening approach. Using a complex, multi-subunit antigen as a model protein, we observed stable CQA profiles independently of the cell culture format during the clonal expansion as well as in the batch and fed-batch processes. In conclusion, we propose an accelerated clone selection approach that can be readily incorporated into various cell line development workstreams, leading to significant reduction of the project timelines and resource requirements. 相似文献
282.
Bin Liu Xin Zheng Jiajun Li Xiong Li Ruimei Wu Jing Yang Wei Liu Gaoping Zhao 《Bioscience reports》2021,41(1)
Objective: The traditional Chinese medicine Caulis Sargentodoxae is widely used in the treatment of ulcerative colitis (UC), but the mechanism remains unknown. The present study aims to reveal its effective components, targets and pathways through network pharmacology and bioinformatics approaches.Materials and methods: Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) was used to identify effective components. The ligand-based targets prediction was achieved through SwissTargetPrediction and TargetNet. UC-related targets were identified using Gene Expression Omnibus (GEO) data and DisGeNET. The common targets of disease and components were constructed and analyzed by PPI network. Lastly, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses are used to explain the functions of these common targets. Components-Targets-Pathways network was visualized and analyzed to further reveal the connection between the components and targets.Results: Eight active components and 102 key targets were identified to play an important role in UC. These targets were related to regulation of protein serine/threonine kinase activity, positive regulation of cell motility, response to molecule of bacterial origin, response to toxic substance, ERK1 and ERK2 cascade, peptidyl-tyrosine modification, inositol lipid-mediated signaling, cellular response to drug, regulation of inflammatory response and leukocyte migration. Moreover, HIF-1 signaling pathway and PI3K-Akt signaling pathway were the key targets involved in UC-related signaling pathways.Conclusion: The eight active components of Caulis Sargentodoxae mainly play a therapeutic role for UC through synergistic regulation of HIF-1 signaling pathway and PI3K-Akt signaling pathway. 相似文献
283.
Cui-Cui Zhao Jing Chen Li-Ying Zhang Hong Liu Chuan-Gui Zhang Yan Liu 《Bioscience reports》2021,41(1)
Triple negative breast cancer (TNBC) is a more common type of breast cancer with high distant metastasis and poor prognosis. The potential role of lamins in cancer progression has been widely revealed. However, the function of lamin B2 (LMNB2) in TNBC progression is still unclear. The present study aimed to investigate the role of LMNB2 in TNBC. The cancer genome atlas (TCGA) database analysis and immunohistochemistry (IHC) were performed to examine LMNB2 expression levels. LMNB2 short hairpin RNA plasmid or lentivirus was used to deplete the expression of LMNB2 in human TNBC cell lines including MDA-MB-468 and MDA-MB-231. Alterations in cell proliferation and apoptosis in vitro and the nude mouse tumorigenicity assay in vivo were subsequently analyzed. The human TNBC tissues shown high expression of LMNB2 according to the bioinformation analysis and IHC assays. LMNB2 expression was correlated with the clinical pathological features of TNBC patients, including pTNM stage and lymph node metastasis. Through in vitro and in vivo assays, we confirmed LMNB2 depletion suppressed the proliferation and induced the apoptosis of TNBC cells, and inhibited tumor growth of TNBC cells in mice, with the decrease in Ki67 expression or the increase in caspase-3 expression. In conclusion, LMNB2 may promote TNBC progression and could serve as a potential therapeutic target for TNBC treatment. 相似文献
284.
Jin Jing Essemine Jemaa Duan Jianli Zhu Jian Cai Weiming 《Plant Cell, Tissue and Organ Culture》2021,145(2):223-238
Plant Cell, Tissue and Organ Culture (PCTOC) - This report focuses on the crucial role of lipids and starch metabolism in the growth and ultrastructure of the cell wall (CW) in rice calli.... 相似文献
285.
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287.
Meiyu Cheng Nan Lin Delu Dong Jiaoyan Ma Jing Su Liankun Sun 《European journal of cell biology》2021,100(1):151144
In response to mitochondrial damage, mitochondria activate mitochondrial dynamics to maintain normal functions, and an imbalance in mitochondrial dynamics triggers multiple programmed cell death processes. Recent studies have shown that phosphoglycerate mutase 5 (PGAM5) is associated with mitochondrial damage. PGAM5 activates mitochondrial biogenesis and mitophagy to promote a cellular compensatory response when mitochondria are mildly damaged, whereas severe damage to mitochondria leads to PGAM5 inducing excessive mitochondria fission, disruption to mitochondrial movement, and amplification of apoptosis, necroptosis and mitophagic death signals, which eventually evoke cell death. PGAM5 functions mainly through protein-protein interactions and specific Ser/Thr/His protein phosphatase activity. PGAM5 is also regulated by mitochondrial proteases. Detection of PGAM5 and its interacting protein partners should enable a more accurate evaluation of mitochondrial damage and a more precise method for the diagnosis and treatment of diseases. 相似文献
288.
289.
The occurrence of accidental mutations or deletions caused by genome editing with CRISPR/Cas9 system remains a critical unsolved problem of the technology. Blocking excess or prolonged Cas9 activity in cells is considered as one means of solving this problem. Here, we report the development of an inhibitory DNA aptamer against Cas9 by means of in vitro selection (systematic evolution of ligands by exponential enrichment) and subsequent screening with an in vitro cleavage assay. The inhibitory aptamer could bind to Cas9 at low nanomolar affinity and partially form a duplex with CRISPR RNA, contributing to its inhibitory activity. We also demonstrated that improving the inhibitory aptamer with locked nucleic acids efficiently suppressed Cas9-directed genome editing in cells and reduced off-target genome editing. The findings presented here might enable the development of safer and controllable genome editing for biomedical research and gene therapy. 相似文献
290.
Parker Camille Zhao Jing Pearce David A. Kovács Attila D. 《Archives of microbiology》2021,203(1):85-96
Archives of Microbiology - Accumulated evidence indicates that the gut microbiota affects brain function and may be altered in neurological diseases. In this study, we analyzed the gut microbiota... 相似文献