Open AccessUltrasound‐microbubble cavitation facilitates adeno‐associated virus mediated cochlear gene transfection across the round‐window membrane
Author(s) -
Zhang Zhen,
Chen Zhengg,
Fan Liqiang,
Landry Thomas,
Brown Jeremy,
Yu Zhiping,
Yin Shankai,
Wang Jian
Publication year - 2021
Publication title -
bioengineering and translational medicine
Language(s) - English
Resource type - Journals
ISSN - 2380-6761
DOI - 10.1002/btm2.10189
Subject(s) - round window , transfection , cochlea , gene delivery , inner ear , genetic enhancement , adeno associated virus , microbiology and biotechnology , perilymph , ultrasound , biophysics , biomedical engineering , chemistry , gene , biology , medicine , recombinant dna , anatomy , vector (molecular biology) , biochemistry , radiology
The round window of the cochlea provides an ideal route for delivering medicines and gene therapy reagents that can cross the round window membrane (RWM) into the inner ear. Recombinant adeno‐associated viruses (rAAVs) have several advantages and are recommended as viral vectors for gene transfection. However, rAAVs cannot cross an intact RWM. Consequently, ultrasound‐mediated microbubble (USMB) cavitation is potentially useful, because it can sonoporate the cell membranes, and increase their permeability to large molecules. The use of USMB cavitation for drug delivery across the RWM has been tested in a few animal studies but has not been used in the context of AAV‐mediated gene transfection. The currently available large size of the ultrasound probe appears to be a limiting factor in the application of this method to the RWM. In this study, we used home‐made ultrasound probe with a decreased diameter to 1.5 mm, which enabled the easy positioning of the probe close to the RWM. In guinea pigs, we used this probe to determine that (1) USMB cavitation caused limited damage to the outer surface layer or the RWM, (2) an eGFP‐gene carrying rAAV could effectively pass the USMB‐treated RWM and reliably transfect cochlear cells, and (3) the hearing function of the cochlea remained unchanged. Our results suggest that USMB cavitation of the RWM is a good method for rAAV‐mediated cochlear gene transfection with clear potential for clinical translation. We additionally discuss several advantages of the small probe size.