Physical and chemical methods for enhancing rapid detection of viruses and other agents

Abstract

Viral replication events can be enhanced by physical, chemical, or heat treatment of cells. The centrifugation of cells can stimulate them to proliferate, reduce their generation times, and activate gene expression. Human endothelial cells can be activated to release cyclo-oxygenase metabolites after rocking for 5 min, and mechanical stress can stimulate endothelial cells to proliferate. Centrifugation of virus-infected cultures can increase cytopathic effects (CPE), enhance the number of infected cells, increase viral yields, and reduce viral detection times and may increase viral isolation rates. The rolling of virus-infected cells also has an effect similar to that of centrifugation. The continuous rolling of virus-infected cultures at < or = 2.0 rpm can enhance enterovirus, rhinovirus, reovirus, rotavirus, paramyxovirus, herpesvirus, and vaccinia virus CPE or yields or both. For some viruses, the continuous rolling of infected cell cultures at 96 rpm (1.9 x g) is superior to rolling at 2.0 rpm for viral replication or CPE production. In addition to centrifugation and rolling, the treatment of cells with chemicals or heat can also enhance viral yields or CPE. For example, the treatment of virus-infected cells with dimethyl sulfoxide can enhance viral transformation, increase plaque numbers and plaque size, increase the number of cells producing antigens, and increase viral yields. The infectivity of fowl plague virus is increased by 80-fold when 4% dimethyl sulfoxide is added to culture medium immediately after infection. The heat shocking of virus-infected cells also has been shown to have a stimulatory effect on the replication events of cytomegalovirus, Epstein-Barr virus, and human immunodeficiency virus. The effects of motion, chemicals, or heat treatments on viral replication are not well understood. These treatments apparently activate cells to make them more permissive to viral infection and viral replication. Perhaps heat shock proteins or stress proteins are a common factor for this enhancement phenomenon. The utility of these treatments alone or in combination with other methods for enhancing viral isolation and replication in a diagnostic setting needs further investigation.

Serum‐free suspension cultivation of PER.C6® cells and recombinant adenovirus production under different pH conditions

“…Virus infection and replication were shown to be affected by culture pH as well (Hughes, 1993;Ross and Sanders, 1979). Alexander and Collins (1975) studied the growth of avian infectious bronchitis virus in chicken kidney cells in a wide pH range of 6.0-9.0.…”

Parainfluenza Viruses

“…Detected is performed by standard IF of the tissue culture cells, typically at 48 h and 5 days. Although variable results have been reported, the majority of data appear to demonstrate improved detection using this method (164). Influenza virus and RSV are the two viruses most widely studied by this method.…”

Spinoculation Triggers Dynamic Actin and Cofilin Activity That Facilitates HIV-1 Infection of Transformed and Resting CD4 T Cells

“…The method was later applied to research in virology, presumably for directly depositing viral particles on cells to enhance infection (13). The mechanical stress introduced during spinning was also believed to be somewhat beneficial to infection, increasing cell permissiveness (17,18). The technique, now termed spinoculation (12), has been widely used with a variety of viruses, such as cytomegalovirus (23), herpes simplex virus (HSV) (31), bluetongue virus (29), hepatitis C virus (43), retroviruses (5,12), and the related HIV-1 (14,22).…”