Abstract

Background: The aim of this study is to provide a basis for the designof appropriate protocols for the shipping and storage of rAAV vectors for experimental laboratory studiesand clinical trials. Material/Methods: rAAV stocks were generated by standard methods and then subjectedto different environments. The transduction efficiency of viral vectors both in vitro and in vivo wasdetermined by luciferase activity and immunohistochemistry. Results: The virus stored at -80 degreesC remained completely stable and had high transduction efficiency. By contrast, the transduction efficiencyof all other groups on 293 cells decreased continuously over time. The transduction efficiency of the-20 degrees C group remained relatively high for the first 5 days, but dropped sharply between days 5and 7. The transduction efficiency for the 4 degrees C group dropped sharply on both days 1 and 7, andcontinued to decrease to 55% of maximum efficiency by the end of the first month. For both the room temperature(RT) and 37 degrees C groups, a sharp fall in efficiency was observed at day 1, and efficiency continuedto decline throughout the experimental period. Data from the in vivo study also revealed that rAAV vectorstored at -80 degrees C remained stable and retained its transduction efficiency. Conclusions: The virusstored at -80 degrees C remained completely stable and retained high transduction efficiency. The implicationsof these findings provide a basis for viral stock portioning and avoidance of freeze-thawing and storingat temperatures above -80 degrees C prior to clinical trials.

Keywords: Cell Line, Cryopreservation, Dependovirus - genetics, genetic therapy, Genetic Vectors, Luciferases - genetics, Rats, Wistar, Recombinant Proteins - genetics, Recombination, Genetic, Temperature, Transduction, Genetic