The Effect And Mechanism Of AGM Against Influenza A Virus

Objective: The effective mechanism of cationic polysaccharide—aminoglucomannan (AGM) with plasmid DNA and some relative factors have been investigated. The AGM was labeled with fluram, the compound of fluram-AGM was explored for its properties and mechanism in trans-membrane in HepG2 cell line. The activity against IFV with AGM in cultured MDCK cells was tested for exploring its antiviral capability and mechanisms.Methods: 1. The polysaccharide-DNA complex were analyzed with agarose gel electrophoresis by the changes of DNA bands position under different effecting factors including pH, strength of ion (NaCl concentration), temperature and the various plasmid DNA. The results were compared with those of control group of other glucide. 2. After the AGM was labeled with fluram, the peripheral blood mononuclear cells (PBMC) and HepG2 cell line were incubated with Fluram-AGM respectively, then the cells of PBMC and HepG2 were observed under fluorescence microscope. 3. The effect of AGM and Ribavirin as control group against cyto-pathogenesis with IFV infection was observed by microscopy and quantitative colorimetric MTT assay in cultured MDCK cells. Decreasing virus yield caused by AGM and Ribavirin has been counted by plaque forming assay in MDCK cells. FQ-PCR and cell ELISA technique were performed for evaluating the inhibitory activity of IFV RNA production and protein expression respectively after the AGM treatment.Results: 1. The new bands appeared in the slow migration positions after cationic polysaccharide treatment, and the content of changed bands of DNA showed the concentrations dependent curve with AGM. The volumes of changed bands of DNA could be affected by pH, temperature, and strength of ion. The effects were same in those with galactosamine treatmet. 2. Both PBMC and HepG2 show indigotic fluorescence under microscopic investigation. The strength of fluorescence is independent of the concentrations of the labeled AGM in the solution. 3. AGM has blocked the pathologic changes in culture cells caused by IFV with a dose-dependent manner. AGM has showed the anti-IFV effects as well as those of Ribavirin. AGM was capable of decreasing both NP-RNA expression and M-proteins expression of IFV.Conclusion: 1. These data suggest that AGM can act with plasmid DNA under proper conditions and exert an influence upon plasmid DNA's solid structure.2. AGM can transport into cell through membrane. 3. The anti-IFV activities of AGM was same as Ribavirin without noticeable cytoxin, its antiviral mechanism might be relevant with the fact that AGM could interact with virus DNA, and to prohibit virus particles assembling and secreting. AGM's chemical stability and bio-histological consistent suggest that it could be a safe, low noxious, effective, antiviral medicine.