Degradation of pseudoviral DNA after infection of mouse cells with polyoma pseudovirions

When mouse cells are infected with [(3)H]-thymidine-labeled polyoma pseudovirions, as much as 11% of the input pseudoviral radioactivity is found in the recipient cell DNA. However, the radioactivity found in the recipient cell DNA virtually disappears when nonradioactive thymidine and deoxycytidine, or D-arabinosyl cytosine, are added to the medium. The radioactivity found in the recipient cell DNA appears to be the result of the breakdown of pseudoviral DNA to precursors of DNA and the utilization of these precursors for the synthesis of cell DNA.

Cytogenetic engineering in vivo: restoration of biologic complement activity to C5-deficient mice by intravenous inoculation of hybrid cells

Splenic macrophages were identified as at least one source of C5 elaboration in normal mice. Hybrid cells were formed from splenic macrophages from C5-deficient mice and either kidney cells from mice with normal amounts of C5 or chicken erythrocytes. These hybrids elaborated C5 in vitro. C5-Deficient mice inoculated with these hybrid cells developed, in their serum, antigenically active mouse C5, as well as both hemolytic and biologic complement activity. These studies demonstrate the feasibility of genetic "repair" in mammals.