West Nile Virus Replication Research Articles

Genetically determined resistance to infection with group B arboviruses. II. Increased production of interfering particles in cell cultures from resistant mice.

The replication of West Nile virus (WNV), a group B arbovirus, in cell cultures derived from inbred C3H/RV mice, which are genetically resistant to group B arbovirus infection, was investigated. These cultures produce lower yields of WNV than do cell cultures from congenic genetically susceptible inbred C3H/He mice. The reduced virus yield from the resistant cultures was not due to inability of these cells to be infected by WNV. Resistant cultures were not more sensitive to the action of exogenous interferon and did not produce endogenous interferon earlier or in larger quantities after WNV infection than did comparable cultures of susceptible cells. Passage of undiluted culture fluid from either resistant or susceptible cultures infected with WNV resulted in a cyclic rise and fall in virus titer. Culture fluid obtained after three serial undiluted passages of WNV in resistant cultures interfered with the multiplication of hamster brain-propagated WNV, whereas interference was not evident with comparable fluid from susceptible cultures.

The growth of arboviruses in organ cultures of mouse meninges and the influence on in vitro virus growth of previous vaccination (36624).

SummaryReplication of three arboviruses, West Nile, Yellow fever and Semliki Forest, occurs in organ cultures of mouse meninges. Replication of West Nile virus is reduced by prior vaccination of the animals. The addition of immune lymphocytes also reduces the yield of West Nile virus from the cultures.