Virus, adsorption

Virus adsorption, entry and uncoating. Drug Disc Today 1 316-324 MeanweU NA, Krystal M (1996b) Taking aim at a moving target - inhibitors of influenza virus. II. 

Because of their interference with the interaction between the viral envelope gpl20 glycoprotein and the cellular CD4 receptor, poly anionic substances not only inhibit virus adsorption to the cells but also block syncytium (giant cell) formation between the HIV-infected (gpl20 + ) cells and uninfected (CD4 + ) cells. Since syncytium formation results in a selective destruction of the CD4+ cells, this syncytium formation may play an important role in the pathogenesis of AIDS (a hallmark of which is a progressive decline of the CD4+ cells). 

There is potential in the anti-HIV field. Polyoxometallates of the Keggin type bind to viral envelope sites on cell surfaces and interfere with virus adsorption. Metal-chelating macrocyclic bicyclam ligands are among the most potent inhibitors of HIV ever described, and there is considerable interest in the role of Zn proteins in the viral life cycle. 

It appears that polyoxometalates are active at the cell surface (354, 355), and they exhibit anti-HIV activity by binding to viral envelope sites (356, 357), interfering with virus adsorption (358). They also inhibit the binding of HIV-l-infected lymphocytes to uninfected lympho-... 

Therapeutic measures. First attempts of a causal treatment consist of zanamavir, an inhibitor of viral neuraminidase, an enzyme necessary for virus adsorption and infection of cells. However, since symptoms of common cold abate spontaneously, there is no compelling need to use drugs. Conventional remedies are intended for symptomatic relief. 

Seaweed Various sulfated polysaccharides extracted from seaweed (i.e., Nothogenia fastigiata, Aghardhiella tenera) inhibit the virus adsorption process. 

Flavonoids Inhibition of virus adsorption by flavonoids such as (-) epicatechin and its 3-0-gallate has been attributed to an irreversible interaction with gpl20 (although these compounds are also known as reverse transcriptase inhibitors). 

Incubate at 37°C for 60-90 min to allow time for virus adsorption, overlay with Eagle s medium containing 5% foetal bovine serum (8 ml/dish 0.4 ml/well). 

Several analogues, which differ from natural sialic add in one or two positions, have been synthesised and tested in a virus-adsorption inhibition assays. 

Gerba, C. P. "Applied and theoretical aspects of virus adsorption to surfaces" Adv. Appl. Microbiol. 1984. 30 133-168. 

Murray, J. P. "Physical chemistry of virus adsorption and degradation on inorganic surfaces" U.S. Environmental Protection Agency, Cincinnati, Ohio. 1980. 

For dilute process streams, product may be lost via adsorption on the membrane. The recovery" of this product may be improved by pretreating the membrane such that most of the adsorption sites are occupied. For example, in the data of Hahn et al16 (Table 2.5), polio virus adsorption on cellulosic "tortuous-pore" membranes was significantly higher than that on polycarbonate "capillary-pore membranes, (i.e.. The virus recovery is low due to adsorption.) The recov ery was improved from 5 to 76% by pretreating the membrane with a beef extract solution. 

To assess the mechanism of SDB, the effect of time of addition of the compound on the reduction of virus yield was examined. As shown in Table 2, SDB was effective when added immediately after virus adsorption... 

Adsorption of enteric viruses on mineral surfaces in soil and aquatic environments is well recognized as an important mechanism controlling virus dissemination in natural systems. The adsorption of poliovirus type 1, strain LSc2ab, on oxide surfaces was studied from the standpoint of equilibrium thermodynamics. Mass-action free energies are found to agree with potentials evaluated from the DLVO-Lifshitz theory of colloid stability, the sum of electrodynamic van der Waals potentials and electrostatic double-layer interactions. The effects of pH and ionic strength as well as electrokinetic and dielectric properties of system components are developed from the model in the context of virus adsorption in extra-host systems. 

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