INVIVO PROMOTER ACTIVITY AND TRANSGENE EXPRESSION IN MAMMALIAN SOMATIC TISSUES EVALUATED BY USING PARTICLE BOMBARDMENT

The particle bombardment method of gene transfer provides an alternative approach for analysis of in vivo promoter activity and transgene expression. Transient expression of the firefly luciferase gene from rive viral and five cellular promoters was assessed after in vivo gene transfer using this method. The relative strengths of these promoters were quantitatively determined in five different rat tissues: skin epidermis, dermis, muscle, liver, and pancreas. Cytomegalovirus immediate early enhancer/promoter activity was consistently the highest in each tissue, whereas other promoters displayed tissue-specific preferences. In liver, the mouse phosphoenolpyruvate carboxykinase and metallothionein promoters were stimulated in vivo by inducing agents at 1 and 5 days posttransfection. In dermis, sustained luciferase activity was observed for over 1.5 years after gene delivery. In vivo transgene expression was also detected in bombarded mouse, rabbit, and rhesus monkey tissues. These results suggest that particle bombardment provides an effective system for studies of in vivo gene transfer and gene therapy.