
Full text loading...
Two components, interferon and residual particles of input virus, contributed to the interfering activity recoverable from mouse embryo cultures treated with molluscum contagiosum virus. Physical and biological techniques were used to distinguish and allow the independent biological assay of each of these components. Cultural conditions greatly affected the induction of interference by molluscum virus. Under optimal conditions, interferon was first detected in treated cultures 6 hr after virus adsorption, reached a maximal value at about 18 hr and then declined rapidly. Virus itself, distinguished from interferon by its acid lability, sedimentability and failure to induce interference in L cells, declined rapidly in activity, during the early hours after adsorption to mouse embryo cells, to about 25% of that calculated to have been adsorbed. Although a direct correlation was not established between the amount of interferon produced and the decline in recoverable virus, a substantial part of this decline was interpreted as a significant biological event akin to ‘eclipse’ of infective virus in a permissive host.