Researchers learn more about ways to regenerate the ear’s hearing cells

Massachusetts General Hospital researchers have made important progress in their ongoing effort to regenerate the inner ear’s hair cells, which convert sound vibrations to nerve impulses. In the Proceedings of the National Academy of Sciences, they report successfully creating a mouse model that allows them to build on earlier findings about the effect of deactivating a protein that controls the growth and division of hair cells. The paper also finds that suppressing the retinoblastoma (Rb) protein has different effects in specific parts of the inner ear.

“In these first studies of the role of the Rb protein in the ears of postnatal mice, we have confirmed that – under the right conditions – mature hair cells can go through the cell cycle and produce new, functioning hair cells. But we’ve also confirmed that you need to block Rb reversibly and at an early stage of development, otherwise the hair cells will die,” says Zheng-Yi Chen of the MGH Neurology Service, the study’s senior author. In 2005 Chen was named to the Scientific American 50, the magazine’s annual list of outstanding leaders, for this continuing research project. Chen is an assistant professor of Neurology of Harvard Medical School.

The research was supported by grants from the National Institutes of Health, the Howard Hughes Medical Institute and a Pfizer/AFAR Innovations in Aging Research Grant.