ABSTRACT
In this study, we investigated the relative localization of some antigenic epitopes in the inner ear. The inner ear protein antigens were extracted from various parts of the guinea pig inner ear. Brain, kidney, lung, heart and liver extracts were also obtained. We found by SDS-polyacrylamide gel electrophoresis that total inner ear extracts separated into three high concentration polypeptide bands with molecular weights of approximately 30, 42, 58 kd and three low density bands of 20, 25 and 35 kd. The 30 kd band was found mainly in the extract of the spiral ganglion and the acoustic nerve in the modiolus. The 42 and 58 kd bands were detected in the extract of the spiral ligament and the stria vascularis. The Organ of Corti and the basilar membrane extract gave rise to three bands of 30, 42 and 58 kd. Twenty-eight of the 75 sera from patients with inner ear disease reacted with the 30 and 58 kd bands of the inner ear protein extracts by immunoblotting. Sixteen of these 28 positive sera were then used to probe immunoblots of the brain, kidney, lung, heart and liver extracts. The 58 kd band was also found in protein extracts of the brain, the lung and the liver. This study suggests that the 30 kd antigenic epitope may be mainly related to the acoustic nerve and that the 58 kd antigenic epitope is not cochlear specific.
Subject(s)
Autoimmune Diseases/immunology , Cochlea/immunology , Ear, Inner/immunology , Epitopes/analysis , Hearing Loss, Sensorineural/immunology , Animals , Basilar Membrane/immunology , Brain/immunology , Electrophoresis, Polyacrylamide Gel , Guinea Pigs , Humans , Immunoblotting , Liver/immunology , Lung/immunology , Molecular Weight , Organ Specificity , Organ of Corti/immunology , Spiral Ganglion/immunology , Stria Vascularis/immunology , Vestibulocochlear Nerve/immunologyABSTRACT
Cytomegalovirus (CMV) is the leading cause of human nonhereditary congenital deafness. The pathogenesis of congenital CMV infection in the auditory system is poorly understood and no suitable animal model is currently recognized. In this study primary maternal CMV infection in guinea pigs during the first or second trimester of pregnancy resulted in congenital infection in 64% of the offspring. Of the congenitally infected neonates, 28% had significant auditory deficits. Within the inner ear, CMV infection was localized in auditory nerve spiral ganglion cells. These findings indicate that congenital CMV infection of the guinea pig results in physiologic and anatomic neuropathology similar to that seen in human infection and provide the first experimental model for congenital CMV-induced sensorineural hearing loss.
