1.Establishment of reporter gene labeled HCV full-length genome replication cell model
Bo GAO ; Shuaizheng JIA ; Jianchun PENG ; Yi WANG ; Wei FAN ; Yintai LI ; Linsheng ZHAN ; Jinbo XU
Chinese Journal of Microbiology and Immunology 2011;31(6):523-527
Objective To establish a stable HCV full-length genome replication cell model which is labeled with reporter gene and easyly to quantify intracellular HCV proteins and RNA level. Methodsneo gene was inserted into Luc-JC1 to make Luc-JC construct. Luc-JC RNA was obtained by in vitro transcription and then delivered into Huh7 cells by transfection. G418-resistant clones of Huh7 cells were obtained by selection. Clones of HCV full-length genome replication cell were confirmed by luciferase activity assay, Western blot and cleaveage of eYFP-MAVS by HCV NS3/4A protease. Then, HCV replication cell colonies were treated by different dose IFN-α in order to observe the change of luciferase activity, HCV protein and RNA level. Results At 3-4 weeks post-transfection, visible colonies were selected and stained by crystal violet. Luciferase activity and HCV NS3, NS5A protein were detected by luciferase activity assay and Western blot, respectively. Subcellular localization of eYFP-MAVS transferred from mitochondria to cytoplasms by cleavage of NS3/4A protease in cell colonies. Luciferase activity, HCV protein and RNA diminished obviously after IFN-α treatment. Conclusion A stable HCV full-length genome replication cell model labeled by reporter gene was successfully established and reporter activity can be used to indicate level of HCV proteins and RNA in cells. This cell model is a useful tool for the study on HCV pathogenesis and the screening of antiviral drugs.
2.Application of StrucGP in medical immunology: site-specific N-glycoproteomic analysis of macrophages.
Pengfei LI ; Zexuan CHEN ; Shanshan YOU ; Yintai XU ; Zhifang HAO ; Didi LIU ; Jiechen SHEN ; Bojing ZHU ; Wei DAN ; Shisheng SUN
Frontiers of Medicine 2023;17(2):304-316
The structure of N-glycans on specific proteins can regulate innate and adaptive immunity via sensing environmental signals. Meanwhile, the structural diversity of N-glycans poses analytical challenges that limit the exploration of specific glycosylation functions. In this work, we used THP-1-derived macrophages as examples to show the vast potential of a N-glycan structural interpretation tool StrucGP in N-glycoproteomic analysis. The intact glycopeptides of macrophages were enriched and analyzed using mass spectrometry (MS)-based glycoproteomic approaches, followed by the large-scale mapping of site-specific glycan structures via StrucGP. Results revealed that bisected GlcNAc, core fucosylated, and sialylated glycans (e.g., HexNAc4Hex5Fuc1Neu5Ac1, N4H5F1S1) were increased in M1 and M2 macrophages, especially in the latter. The findings indicated that these structures may be closely related to macrophage polarization. In addition, a high level of glycosylated PD-L1 was observed in M1 macrophages, and the LacNAc moiety was detected at Asn-192 and Asn-200 of PD-L1, and Asn-200 contained Lewis epitopes. The precision structural interpretation of site-specific glycans and subsequent intervention of target glycoproteins and related glycosyltransferases are of great value for the development of new diagnostic and therapeutic approaches for different diseases.
Humans
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B7-H1 Antigen
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Glycosylation
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Polysaccharides/metabolism*