Park Albert H, Gifford Thomas, Schleiss Mark R, Dahlstrom Lisa, Chase Shane, McGill Lawrence, Li Wenhua, Alder Stephen C
Division of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Utah, 50 N Medical Dr, Bldg 3C, Ste 120, Salt Lake City, UT 84132, USA.
Arch Otolaryngol Head Neck Surg. 2010 Jan;136(1):48-53. doi: 10.1001/archoto.2009.210.
To develop an animal model for cytomegalovirus (CMV)-induced sensorineural hearing loss.
Guinea pig model.
University of Utah otolaryngology research labs.
Thirty-one Hartley guinea pig pups were divided into 4 groups. Group 1 pups were delivered from pregnant dams inoculated with 1 x 10(5) plaque-forming units (PFU) of guinea pig CMV (gpCMV). Group 2 and group 3 pups were delivered from pregnant dams inoculated with higher doses of 2 and 4 x 10(5) PFU of gpCMV, respectively. Group 4 pups, the control group, were delivered from uninoculated dams.
All groups underwent weekly auditory brainstem response studies. Six weeks after delivery, the brain, cochlea, salivary glands, lungs, liver, and kidneys were harvested. All tissue except the cochlea was analyzed for histologic evidence of the virus. All tissue underwent polymerase chain reaction (PCR) to detect gpCMV.
Seven of the 19 (37%) inoculated pups developed a 30-dB hearing loss; none of the animals in the control group had a worse click threshold than 20 dB. Group 1 pups demonstrated statistically significant asymmetric hearing loss. All 3 inoculated groups showed evidence of progressive hearing loss over time. The control group did not demonstrate evidence of progressive threshold worsening. The PCR testing detected gpCMV in the cochleas of group 2 and group 3 animals.
We have successfully demonstrated elevated auditory brainstem response click thresholds with characteristics of progressive and asymmetric loss that have been reported in clinical reports of congenital CMV infection. We also detected gpCMV via PCR testing in the cochleas of inoculated pups.
