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Published on: March 5, 2018
Biodistribution and general safety of a naked DNA plasmid, GTU-MultiHIV, in a rat, using a quantitative PCR method
Mari Tuomela1, Maria Malm, Mika Wallen
1FIT Biotech Plc, Biokatu 10, FIN-33520 Tampere, Finland. mari.tuomela@fitbiotech.com
Abstract:
We studied the general safety, biodistribution and persistence of a naked DNA plasmid in a rat model using intramuscular, intradermal and intravenous routes of administration. Clinical signs were followed up throughout the study and at the necropsy. Tissue samples were collected at the necropsy at 2, 14 and 28 days after injection of 200 microg of plasmid DNA and analysed with validated quantitative polymerase chain reaction (QPCR). The plasmid (GTU-MultiHIV) was shown to be well tolerated and no clinical observations related to the vaccine were found. Within 2 days after the intramuscular and intradermal injections, the plasmid could be detected in the lymph nodes and also at 14 days in a few test animals. The quantitative PCR analysis indicated that in positive lymph nodes one of 15-213 dendritic cells could be carrying the plasmid. No plasmid was detected in gonads or brain samples in any of the study groups. In intramuscular and intradermal administration, low amounts of the plasmid DNA persisted at the injection site 28 days after the injection, whereas a complete clearance with intravenous route was observed already at 14 days. The results show that the GTU-MultiHIV plasmid is safe and suitable for human clinical trials.
Insights
This study assessed the safety and distribution of a naked DNA plasmid (GTU-MultiHIV) in rats. The plasmid demonstrated good tolerability and localized persistence, suggesting suitability for human trials.
Area of Science:
- Biotechnology
- Immunology
- Pharmacology
Background:
- Naked DNA plasmids are utilized in vaccine development.
- Understanding plasmid biodistribution and persistence is crucial for safety assessments.
Purpose of the Study:
- To evaluate the general safety, biodistribution, and persistence of the GTU-MultiHIV DNA plasmid.
- To assess the plasmid's behavior following intramuscular, intradermal, and intravenous administration in a rat model.
Main Methods:
- Rats were administered 200 microg of GTU-MultiHIV plasmid via different routes.
- Clinical signs were monitored, and tissue samples were collected at 2, 14, and 28 days post-injection.
- Quantitative polymerase chain reaction (QPCR) was used to analyze plasmid presence in tissues.
Main Results:
- The GTU-MultiHIV plasmid was well tolerated with no observed adverse clinical signs.
- Plasmid DNA was detected in lymph nodes within 2 days after intramuscular and intradermal administration, persisting in some animals up to 14 days.
- Low levels of plasmid DNA persisted at injection sites for 28 days after intramuscular/intradermal administration, while complete clearance was observed by 14 days after intravenous administration.
- No plasmid was detected in gonads or brain samples.
Conclusions:
- The GTU-MultiHIV DNA plasmid exhibits a favorable safety profile.
- The biodistribution and persistence data support the suitability of this plasmid for future human clinical trials.
