Viral solubilization

The adamantane moiety is of medicinal chemical interest because of its inertness, compactness relative to lipid solubilizing character, and symmetry. Considerable interest, therefore, was engendered by the finding that amantadine (78) was active for the chemoprophylaxis of influenza A in man. There are not many useful chemotherapeutic agents available for the treatment of communicable viral infections, so this finding led to considerable molecular manipulation. The recent abrupt end of the National Influenza Immunization program of 1976 prompted a new look at the nonvaccine means for prophylaxis or treatment of respiratory tract infections due to influenza A, especially in that the well-known antigenic shift or drift of the virus obviates usefulness of the vaccine but not amantadine. 

The systematic study of how detergents solubilize the viral proteins laid the basis for our understanding of how the viral particle is built. The... 

The spike protein complex of the alphaviruses appears to be assembled in the ER. Cross-linking studies of Triton X-lOO-solubilized viral proteins have shown that the p62 and El proteins are linked together to form a complex in the ER (Ziemiecki et al.. 1980). The topology of these complexes is the reverse of that in the viral particle the spikes are within the lumen of the ER and the internal domain of E2 is on the cytoplasmic side of the ER membrane. 

Purification of a variety of viral sialidases (influenza and paramyxovirus) after solubilization by proteases or detergents has been exten-... 

Since the viral replicase has been recently solubilized and purified (see next chapter of this book), it will be soon possible to check the proposed model by readily designable experiments. 

For the incorporation of viral membrane proteins into the ISCOM matrix, virus particles are usually solubilized with detergent, in order to obtain them in non-com-plexed monomeric forms. 

Larin and Gallimore [86] have provided evidence to show that if viral protein is solubilized by surfactants this may result in loss or enhancement of specific viral antigenicity. Treatment of influenza virus with Triton X-100 significantly enhances the antigenicity of viral protein as judged by virus neutralization and haemagglutination inhibition tests similar treatment by Tween 80, NaDS and deoxycholate led to a partial or complete loss of immunogenicity. 

It can be seen then that the metabolic state of the cell is an important factor influencing surface membrane functions. Where viral transformation causes cancer-like properties, metabolic control at the nucleic acid level is likely, although viral-host interactions seem more complex than first theorized (Altman and Katz, 1976). Receptors for enteroviruses have been reported and shown to be specific for various viral strains. Susceptibility to viral infection is correlated with the presence of receptor sites on intracellular membranes as well as on the cell surface. Chemically, virus receptors solubilized from plasma membranes have been determined to be lipoproteins, with the protein moiety being most important in determining receptor activity (McLaren et al., 1968). A review of cell membrane receptors for viruses, antigens and... 

Viral membrane sialidases have been solubilized with the aid of detergents or proteolytic enzymes such as pronase or trypsin (Drzeniek et al., 1966 Laver, 1978). The intact influenza virus sialidase (about 240 kDa) can be solubilized... 

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