Macrophage inflammatory proteins in cytomegalovirus-related inner ear injury.
OBJECTIVE
Inner ear inflammation triggered by CMV infection may play a role in CMV-related auditory pathogenesis. The purpose of the study was to determine if a virally encoded macrophage inflammatory protein played a role in CMV-related hearing loss.


METHODS
Mutagenesis was performed with deletion of a guinea pig CMV macrophage inflammatory protein. Intracochlear inoculations were performed on three groups of animals (n = 18). Group 1 received sterile viral media, Group 2 received wild-type CMV virus, and Group 3 received "knockout" (KO) virus with a deleted immunomodulation gene. Baseline and postinoculation ABRs were obtained. ELISA and PCR were performed and temporal bones examined.


METHODS
Eighteen guinea pigs.


RESULTS
The KO group had significantly better hearing than the WT group. There were no significant differences between the KO and sham groups. The WT group had significant hearing loss at all frequencies. Inflammation and fibrosis were noted in the WT temporal bones only.


CONCLUSIONS
Virally encoded macrophage inflammatory proteins appear to play a significant role in CMV-related hearing loss.
Schraff
Scott A
SA
Department of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229-3039, USA. Scott.Schraff@CCHMC.org
Schleiss
Mark R
MR
Brown
David K
DK
Meinzen-Derr
Jareen
J
Choi
K Yeon
KY
Greinwald
John H
JH
Choo
Daniel I
DI
D000818:Animals; D001309:Auditory Threshold / Q000502:physiology; D054405:Chemokine CCL3 / Q000235:genetics / Q000502:physiology*; D003638:Deafness / Q000821:virology; D004195:Disease Models, Animal; D016057:Evoked Potentials, Auditory, Brain Stem / Q000235:genetics / Q000502:physiology; D005355:Fibrosis; D017353:Gene Deletion; D006168:Guinea Pigs; D034381:Hearing Loss / Q000821:virology; D007762:Labyrinthitis / Q000821:virology*; D016296:Mutagenesis / Q000235:genetics; D019211:Roseolovirus / Q000235:genetics / Q000276:immunology*; D019349:Roseolovirus Infections / Q000276:immunology*; D012533:Scala Tympani / Q000473:pathology; D013701:Temporal Bone / Q000473:pathology; D019562:Viral Load; D014764:Viral Proteins / Q000235:genetics / Q000502:physiology*; D014766:Viremia / Q000382:microbiology
D054405:Chemokine CCL3; D014764:Viral Proteins