Predominance of Auditory But Not Vestibular Deficits in a Mouse Model of Congenital Cytomegalovirus Infection.

Abstract

Objectives: The aim of this study was to investigate the auditory and vestibular consequences of congenital cytomegalovirus (cCMV) infection in a C57BL/6 mouse model. This model, established via intraperitoneal inoculation, was designed to mimic clinical phenotypes.

Methods: A cCMV infection model was developed by intraperitoneally inoculating C57BL/6 mice with murine cytomegalovirus. Auditory and vestibular functions were evaluated using auditory brainstem response tests, as well as open field, swim, and rotarod assessments. Histologic analysis of the inner ear was also conducted.

Results: The study successfully established a cCMV infection model in C57BL/6 mice. Auditory deficits of varying severity and laterality were observed, mirroring the clinical spectrum seen in humans. In contrast, vestibular function was minimally affected and did not correlate with auditory deficits. Histopathologic examination revealed predominant damage to spiral ganglion neurons, while the vestibular organs remained relatively intact.

Conclusion: Our optimized mouse model effectively recapitulates the inner ear manifestations of human cCMV infection. The predominance of auditory over vestibular deficits provides valuable insights for developing targeted therapeutic interventions for cCMV-related inner ear sequelae.