Specific uptake of plasmid DNA without reporter gene expression in Atlantic salmon (Salmo salar L.) kidney after intramuscular administration

Immunogenic and protective effects of an oral DNA vaccine against infectious pancreatic necrosis virus in fish

“…The isolation of pDNA in such organs indicates that pDNA avoids local degradation [16]. There is significant information on the distribution of plasmids after intramuscular, intraperitoneal and intravenous injection [27], as well as by immersion in rainbow trout, demonstrating that both the formulation and route of administration influence the efficiency of vaccine distribution and gene expression. Indeed, after intraperitoneal injection of a vaccine formulated with liposomes, pDNA can be detected by PCR in the head kidney, liver and muscle at the injection site, while only muscle tissue at the injection site was positive when naked DNA was used [30].…”

“…We proved that pDNA was not degraded by nucleases or pH in the gastrointestinal tract, as the target gene was expressed in the fish for at least 60 days. The kidney seems to be an important organ for the uptake and expression of DNA vaccines since pDNA uptake and transgene expression have both been demonstrated in kidney macrophages from several fish species [27,31,32]. We previously demonstrated VP2 gene expression in the kidneys of brown trout 30 days post-vaccination when studying the innate immune response induced by the pcDNA-VP2 vaccine administered by injection [1].…”

What happens to the DNA vaccine in fish? A review of current knowledge

“…Local degradation of pDNA at the administration site after i.m. administration has been observed in both Atlantic salmon [182] and Atlantic cod [183]; however, the causal Figure 2 Plasmid DNA may be distributed to four different compartments in fish after intramuscular administration. At the administration site, some pDNA may be locally degraded and transferred to the urinary excretion system, and a fraction of the pDNA may be transferred to the circulatory system and distributed to other organs and tissues.…”

Formation and oral administration of alginate microspheres loaded with pDNA coding for lymphocystis disease virus (LCDV) to Japanese flounder

“…We propose that pDNA-loaded alginate microspheres were distributed to immune tissues via the blood. These data suggest that oral administration of alginate microspheres loaded with pDNA might induce antibody production in the fish for a longer time period than naked pDNA, where degradation of the pDNA occurred in a short time following injection [17,39,40].…”