Effect of Magnesium on Replication of Rhinovirus HGP

Abstract

It is known that plaque formation by some rhinoviruses is greatly enhanced by increasing the concentration of MgCl 2 . The mechanism of this action was studied by investigating the effects of MgCl 2 on rhinovirus HGP adsorption, growth, clumping, thermal stability, and cell susceptibility to viral cytopathic effect. The latent period was at most 7 hr, whether virus was propagated in cells maintained in 0.8 or 30 m m MgCl 2 , but virus release was 8- to 310-fold greater in the presence of 30m m MgCl 2 , depending on initial multiplicity. Intracellular virus content appeared unaffected by Mg ++ and reached maximal yield (plateau phase) at about 10 hr. Viral adsorption was increased when cells were maintained in 30m m Mg ++ . It is likely that the two effects of magnesium, enhanced adsorption and increased virus release, both contribute to enhancement of plaque formation.