Transfer of a human preproinsulin gene containing plasmid into non-pancreatic mammalian cells.

A recombinant plasmid containing the human preproinsulin gene fused to the mouse metallothionein-I-promoter was transferred into Vero cells from a monkey kidney cell line by protoplast fusion. The transient formation of immunoreactive insulin was demonstrated by RIA and studied in the absence and in the presence of zinc and cadmium ions. The recombinant plasmid was encapsulated into reverse-phase evaporated vesicles and the influence of the sonication time on the encapsulated DNA has been studied. It was demonstrated that, although DNA fragmentation occurs, at least a part of the encapsulated DNA retains its biological activity.