The calcium ionophore A23187 evokes and potentiates antiviral activity of interferon

Calcium ionophore A23187, which causes a rapid efflux of Ca2+ from cells, evokes an antiviral response in mouse LB, simian COS-1, Hela, human amniotic (U), baby hamster kidney (BHK), and VERO cells against Sindbis (SBV) and vesicular stomatitis (VSV) viruses. The degree of antiviral activity depends on the type of cell, virus, and the dose of A23187. A23187 inhibits the production of infectious VSV; however, VSV particle production was not significantly inhibited as measured by viral RNA and viral proteins. The VSV released from the A23187-treated cells is deficient in VSV glycoprotein (G) and membrane (M) protein. A23187 potentiates the antiviral activity of interferon (IFN) against SBV and VSV in mouse LB and human U cells. It is possible to postulate that a change in intracellular Ca2+ may play an important role in the antiviral activity of IFN.