Figure 6.

Delivery of siRNA by the SEP device results in targeted gene knockdown of reporter gene in dermal tissue. Guinea pig skin was injected intradermally with 25 µg of DNA plasmid-expressing GFP (pgWIZ-GFP) left untreated, 25 µg of DNA plasmid-expressing GFP and immediately pulsed with the SEP device or plasmid mixed with either siRNA-GFP or siRNA-Luc (20 µg) and immediately pulsed with the SEP device. (a) Skin biopsies were harvested 24 hours later and observed under bright light for determination of treatment site location or fluorescent microscopy for determination of GFP positive signal. (b) GFP pixel density was determined using pixel counting software as described (see Materials and Methods). GFP, green fluorescent protein; luc, luciferase; SEP, surface electroporation; siRNA, small interfering RNA.