title: Stability of infectious recombinant adeno-associated viral vector in gene delivery.
abstract: BACKGROUND
  The aim of this study is to provide a basis for the design of appropriate protocols for the shipping and storage of rAAV vectors for experimental laboratory studies and clinical trials.
  
  
  METHODS
  rAAV stocks were generated by standard methods and then subjected to different environments. The transduction efficiency of viral vectors both in vitro and in vivo was determined by luciferase activity and immunohistochemistry.
  
  
  RESULTS
  The virus stored at -80 degrees C remained completely stable and had high transduction efficiency. By contrast, the transduction efficiency of 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 5 and 7. The transduction efficiency for the 4 degrees C group dropped sharply on both days 1 and 7, and continued 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 continued to decline throughout the experimental period. Data from the in vivo study also revealed that rAAV vector stored at -80 degrees C remained stable and retained its transduction efficiency.
  
  
  CONCLUSIONS
  The virus stored at -80 degrees C remained completely stable and retained high transduction efficiency. The implications of these findings provide a basis for viral stock portioning and avoidance of freeze-thawing and storing at temperatures above -80 degrees C prior to clinical trials.
authors.affiliation: Gene Therapy Laboratory, University of Hong Kong, Hong Kong, China. rxua@hkucc.hku.hk
authors.forename: Ruian
authors.initials: R
authors.lastname: Xu
authors.forename: Mehdi
authors.initials: M
authors.lastname: Rahimi
authors.forename: Hsu
authors.initials: H
authors.lastname: Ma
authors.forename: Peter
authors.initials: P
authors.lastname: Fung
authors.forename: Chunqi
authors.initials: C
authors.lastname: Chang
authors.forename: Sue
authors.initials: S
authors.lastname: Xu
authors.forename: Matthew
authors.initials: M
authors.lastname: During
mesh_terms: D000818:Animals; D002460:Cell Line; D015925:Cryopreservation; D000229:Dependovirus / Q000235:genetics*; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D066298:In Vitro Techniques; D008156:Luciferases / Q000235:genetics; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000235:genetics; D011995:Recombination, Genetic; D013696:Temperature; D014161:Transduction, Genetic
chemical_list: D011994:Recombinant Proteins; D008156:Luciferases