In Vivo Transgene Expression in the Pancreas by the Intraductal Injection of Naked Plasmid DNA

Abstract

Patients with type I diabetes, which is caused by the destruction of pancreatic islets, now require regular therapeutic injections of insulin. The use of transgene therapy represents an alternate and potent strategy for the treatment of type I diabetes. However, only a limited number of studies regarding in vivo gene delivery targeting the pancreas and islets have been reported. Here, we report on the possibility of in vivo transgene expression in the pancreas by the intraductal injection of naked plasmid DNA (pDNA). Gene expression activities were detected in the pancreas of mice after the injection of naked pDNA encoding luciferase into the common bile duct. We then investigated the effects of injection dose, volume, and speed on gene delivery and determined the optimal conditions for the delivery of pDNA to the pancreas. Exogenous luciferase mRNA was detected in the pancreatic islets by reverse transcription PCR analysis. Moreover, no injury was detected in the liver, the common bile duct, or the pancreas over time after the injection. These findings indicate that the intraductal injection of naked pDNA promises to be a useful technique for in vivo gene delivery targeted to pancreatic tissue and islets.

Gene Therapy for Overactive Bladder: A Review of BK-Channel α-Subunit Gene Transfer

“…41 Organs and systems successfully targeted by naked pDNA in preclinical and clinical studies have included the heart, central nervous system, pancreas, penis, and skeletal muscle. 41,[45][46][47] URO-902 is a 6880-base-pair naked pDNA incorporating a DNA sequence synthesized from the messenger RNA (mRNA) that encodes the human BK channel αsubunit (Figure 2). 21,48 To ensure robust expression of the encoded protein in eukaryotic cells, the α-subunit code is flanked at its upstream end by a CMV promoter (from cytomegalovirus) to initiate DNA transcription and at its downstream end by a polyadenylation signal (from the bovine growth hormone gene) to terminate transcription and protect the transcript from enzymatic degradation.…”

Validation of a mitochondrial RNA therapeutic strategy using fibroblasts from a Leigh syndrome patient with a mutation in the mitochondrial ND3 gene

“…In addition, unlike DNA, it would be predicted to not have a sustained effect and would not be expected to induce serious side effects. Concerning targeting the nucleus, research related to DNA delivery was previously a mainstream effort [11][12][13][14][15] , but due to technological innovations, the use of in vitro enzyme reactions to produce RNA are now become simpler and less expensive, and many researchers have now focused their research interest on the delivery of RNA [8][9][10] . Regarding mitochondria, the delivery of DNA and RNA have not been extensively reported, but a procedure involving RNA delivery would be more likely to be useful for the same reason as it is in nuclear-targeted research.…”

Extracellular vesicle expansion of PMIS‐miR‐210 expression inhibits colorectal tumour growth via apoptosis and an XIST/NME1 regulatory mechanism

“…Whether for vaccines or therapeutic treatments, plasmid DNA has been successfully injected into muscle, pancreas, brain and liver. 77 , 78 , 79 , 80 , 81 , 82 , 83 However, direct injection into the blood has low efficiency and the plasmid DNA is rapidly degraded and a disadvantage of direct injection of naked plasmid DNA in some cases is that it can be degraded prior to high levels of gene expression.…”