Enhancement of Infectivity of Cell-Free Varicella-Zoster Virus with Diethylaminoethyl-Dextran

Abstract
Diethylaminoethyl-dextran (DEAE-D) increased the cytopathic effect of varicella-zoster (V-Z) virus, and the plaquing efficiency observed 4 days after infection of MRC-5 human diploid fibroblasts with cell-free V-Z. When DEAE-D was added either before or after virus inoculation there was an increase of two- to fivefold in the number of plaques. The highest value of enhancement was obtained when DEAE-D was added to the maintenance medium at a final concentration of 5.0 μg/ml immediately after a period of virus adsorption. DEAE-D also had an augmenting effect on the adsorption and penetration kinetics of cell-free V-Z virus.