and arthritis in humans and is a model virus for Equine encephalitis virus, which can cause
inflammation of the brain that can be fatal. By studying Sindbis virus, we have the potential to
find compounds that can be applied to Equine encephalitis virus and lower viremia. Recently,
we have found that protecting osmolytes reduce the infectivity of a nonenveloped virus, and
therefore we have applied this same method to Sindbis virus, an enveloped virus. Infection of
Sindbis virus on baby hamster kidney (BHK-21) cells was studied with an MTT cell viability
assay. Osmolytes and salts were added at different times to cells infected with Sindbis virus
and a reduction in infectivity of BHK cells was found. The addition of 0.05M ammonium sulfate
has the ability to double the number of viable cells, when added to either the virus prior to cell
infection, or added at the same time as cell infection. It has been shown by others that cell
bound heparin sulfate is important in Sindbis infection of BHK cells. We are likely reducing the
interaction of the virus with the cells by saturating the heparin sulfate binding site. The addition
of simple compounds can reduce infectivity levels caused by Sindbis virus and can possibly be
applied to other enveloped viruses such as Equine encephalitis virus.