tailieunhanh - Báo cáo y học: " Differences in the mannose oligomer specificities of the closely related lectins from Galanthus nivalis and Zea mays strongly determine their eventual anti-HIV activity"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: Differences in the mannose oligomer specificities of the closely related lectins from Galanthus nivalis and Zea mays strongly determine their eventual anti-HIV activity. | Hoorelbeke et al. Retrovirology 2011 8 10 http content 8 1 10 RETROVIROLOGY RESEARCH Open Access Differences in the mannose oligomer specificities of the closely related lectins from Galanthus nivalis and Zea mays strongly determine their eventual anti-HIV activity 1 2 3 1 12 Bart Hoorelbeke Els JM Van Damme Pierre Rougé Dominique Schols Kristel Van Laethem Elke Fouquaert Jan Balzarini1 Abstract Background In a recent report the carbohydrate-binding specificities of the plant lectins Galanthus nivalis GNA and the closely related lectin from Zea mays GNAmaize were determined by glycan array analysis and indicated that GNAmaize recognizes complex-type N-glycans whereas GNA has specificity towards high-mannose-type glycans. Both lectins are tetrameric proteins sharing 64 sequence similarity. Results GNAmaize appeared to be 20- to 100-fold less inhibitory than GNA against HIV infection syncytia formation between persistently HIV-1-infected HuT-78 cells and uninfected CD4 T-lymphocyte SupT1 cells HIV-1 capture by DC-SIGN and subsequent transmission of DC-SIGN-captured virions to uninfected CD4 T-lymphocyte cells. In contrast to GNA which preferentially selects for virus strains with deleted high-mannose-type glycans on gp120 prolonged exposure of HIV-1 to dose-escalating concentrations of GNAmaize selected for mutant virus strains in which one complex-type glycan of gp120 was deleted. Surface Plasmon Resonance SPR analysis revealed that GNA and GNAmaize interact with HIV IIIB gp120 with affinity constants KD of nM and 34 nM respectively. Whereas immobilized GNA specifically binds mannose oligomers GNAmaize selectively binds complex-type GlcNAcb1 2Man oligomers. Also epitope mapping experiments revealed that GNA and the mannose-specific mAb 2G12 can independently bind from GNAmaize to gp120 whereas GNAmaize cannot efficiently bind to gp120 that contained prebound PHA-E GlcNAcb1 2man specific or SNA NeuAca2 6X specific . Conclusion The markedly