Fig. 4. Southern blot analysis of tissues 48 h after intramuscular administration of native pDNA (1 mg kg^–1 body mass). SC, supercoiled topoform; OC, open-circular topoform,; L, linear topoform. All topoforms of pDNA (R70pRomiLuc) were detectable in all the investigated tissues, but degradation products were only visible in samples from the injection site